Rotary-engine valve



Sept. 30, 1924. 1,509,885

H. L. F. TREBERT ROTARY ENGINE VALVE Original Filed Aug. 27 1917Patented Sept. 30, 1924.

UNITED STATES I 1,509,885 PATENT OFFICE.

HENRY L. I. 'IREBEB'I, OF WEST BIIOOMFIELD, NEW YORK, ASSIGNOR TOTREBERT AIRPLANE MOTOR COHIANY, INC 01' PENN YAN, NEW YORK, ACORPORATION or new YORK.

ROTARY-ENGINE VALVE.

Original application iiled August 27, 1817, Serial R0. 188,342. Dividedand this application filed July 26,

To all whom it may concern:

Be it known that I, HENRY L. F. TREBERT, a citizen of the United States,residing at West Bloomfield, in the county'of Ontario to theaccompanying drawings, forming a part of this specification, and to thereference numerals marked thereon.

'My present invention relates to internal combustion engines and moreparticularly to 16 gas engines of the rotary type, and it has for itsobject to provide a simple and efficient valve gear for such engine soconstructed and arranged that the valve will be kept cool by the passageof air current induced by the rotation of the engine. A further objectof the invention is to keep down the temperature of the whole cylinderhead in which the valves are located. To these and other ends theinvention consists in certain improvements and combinations of parts,all as will be hereinafter more fully described, the novel featuresbeing pointed out in the claim at the end of the specification.

In the drawings:

Figure 1 is a transverse sectional view through a rotary gas engineconstructed in accordance with and illustrating. one embodiment of myinvention, the plane of the section being centrally of the exhaust valveof the engine, and

Figure 2 is a fragmentary section on the line 2-2 of Figure 1.

Similar reference numerals throughout the several views indicate thesame parts.

The engine illustrated as an embodiment of my invention has beendesigned particularly for aeroplane use, and I will first briefly recitesome of its main characteristics as disclosed in m pending application,Serial No 188,342, led August 27, 1917, of

which this is a division. It is a sixteen cylinder engine, air cooled.The fixed element is ,a crank shaft having only two cranks or crankcenters andthe pistons are constructed in pairs, the units of which arerelatively fixed and operate together although no two cylinders. aretimed exactly the same. The

, fuel supply reaches the cylinders, ultimately,

in the manner of the ordinary stationary Serial 1T0. 487,765.

engine, there being, in the present instance, a manlfold for each fourcylinders. There is an individual exhaust for each cylinder,

through which an air current is forced by the rotation of the engine tocool the exhaust valve. Puppet-valves are used and they are actuated bycam shafts and rocker arms with one cam shaft to each four cylinders,but the valve gear is so constructed that the valves escape the effectof centrifugal force, hitherto a source of trouble in rotary engines.

Referring more particularly to the drawings, 1 indicates a crank shaftthat constitutes a central fixed element of the engine. The crank isenclosed within a crank case 8 that is rectangular and made in halves,as usual, with a seam at 9 in the plane of the axis of the engine.Bolted to the crank case in longitudinal rows of four each and projecting radially at 90 angle from each other are the cylinders 23.

Bolted or otherwise suitably secured on the outside of the case 8 are aplurality of radially disposed cylinders 23 ribbed for air cooling. Theyare arranged in longitudinal and circumferential rows of four each andin the circumferential rows, as shown in Figure 1, the axes of thecylinders all lie in the same transverse plane. The cylinders aretherefore opposed in pairs and the pistons 27 of each pair arerelatively immovable and rigidly connected together by connecting rods24 in conjunction with an intermediate cross head 25. The pistons, onthe one hand, and their connecting rods on the other, are thereforerelatively ofi'set so that the connections between each two pairs ofpistons of the four cylinders whose axes lie in the same transverseplane, can cross each other without interference and be connected to thesame crank center 6 as hereinafter described and as shown in Figure 1.The cross heads 25 are fitted with bronze shoes 31 that are adapted totravel upon hardened steel way plates 32 on the interior of the crankcase and there is also a relative reciprocation of the crank 1 withinthe cross head through the medium of sliding journal blocks 33 as willbe understood in a general way but the details of this part of theengine structure are not essential to the present invention.

In the practice of the present invention, the cylinder heads 34 are castin pairs for v with the intake ports 35 by means of a hea 39 on eachpair of cylinders are the branches of a manifold 40. There is one suchmanifold between each two longitudinal rows of cylinders, or four in alland each manifold is supplied by a longitudinally extending pipe 41connected to a suitable-fuel supply as shown in my said pendingapplication.

The exhaust ports 36 deliver into a chamber 48 that is formed in thepresent instance by a transverse pipe 49 cast inte rally with v thecylinder head and open at th ends. Its longitudinal extent is such thatas the engine rotates a stron air current vvill be forced into theprefera ly expanded end 50 and out at the end 51, together with theproducts of combustion from the exhaust port. This tends to keep thecylinder head cool and effectively prevents the exhaust valve, 38 fromover-heating. To this end, the stem 51"'of the valve reciprocates in abearing 52 disposed transversely across the chamber 48 where it receivesthe full effect of the blast of air.

Both of the valves 37 and 38 open inwardly toward the center of rotationon radial lines and close in an outward direction, thestem 53 of eachintake valve being also guided in a bearing) 54 in the cylinder head butbeing cooled the current of fuel. Springs 55 tend to c ose the valves,as usual, but they are opened in a ositive manner for the reason thatwith t e arrangement described, centrifugal force is always acting toclose the valves and hence should preferably work with the s ringsinstead of against them. This e ect of centrifugal action on the valveshas always resented difficulties in rotary en ines, an I have found 1tve diflicult i .not impossible to operate a va ve with a spring againstcentrlfugal force in a uniform manner, it being borne in mind that theressuredue to centrifugal action varies with the speed of the en me.

o tpositively open the valves in an inward irection, I employ a camshaft 56 for each longitudinal row of cylinders, there being one suchcam shaft between each two rows. These shafts are su ported in bearingson arms 58 extended from the fuel supply pipes that are secured to thecrank case 8 as at 59.

Cams 69 on the cam shafts cooperate with rollers 70 on bell crank rockerarms 71 suitably journaled on the cylinder head castngs 34. In thepresent instance, they turn in bosses 72 on the exhaust tubes 49 and thearms of the levers rest upon the valve stems 51 and 53 in the usualmanner.

I claim as my invention:

In' a rotary gas engine, the combination with a fixed central elementand a plurality of rotatable radial cylinders arranged side by side,axiall of the fixed element, in pairs, of cylind er heads castintegrally for each pair of cylinders and each comprisin a fue intakechamber common to both cy inders and individual exhaust pipes for thelatter, which pipes are-so disposed as to be traversed internally by aircurrents superinduced by the movement of the cylinders about the fixedelement.

HENRY L. F. TREBERT.

